The simple premise fails if a single pilot is allowed to occupy a cockpit in front of an IRCD, are we simple enough to call a pilot who wants to sink a ship with hundreds of innocent people at no control of their fate a terrorist? He may have no agenda other than suicide and a complete level of apathy for the people he takes with him. Simply a selfish agenda to make a big name for himself so others may have empathy for his sick reasoning. Sure the IRCD may have deterred possible action by terrorists but the fact is it to this day has only contributed to an act of genocide.
Simple and proven procedures may have prevented this. You create any measure of safety it certain that someone will find a way to take advantage of or circumvent it's intent.
1 out of thousands/**** happens et cetera, it is impossible to protect all good willed citizens of this earth from evil.